To power this self sufficient ambiant lamp, only a few drops of water are enough. Energy is produced by an hydro-electric battery composed of a carbon stick coated with magnesium powder. The water generates an electro chemical reaction that generates light.This autonomous object increases people awareness by including its participation in the energy production process. Water this lamp to feed it, like a living organism which need care. In addition to its ecological aspect, WAT is a poetic proposal that surprises our behavioral habits reliance in an electrical device.